target/linux/gemini/patches-4.14/0026-power-gemini-poweroff-Avoid-spurious-poweroff.patch

   1 From da443bc125265cae24a0e5f7d1c7bba196a9319f Mon Sep 17 00:00:00 2001
   2 From: Linus Walleij <linus.walleij@linaro.org>
   3 Date: Thu, 22 Feb 2018 08:34:35 +0100
   4 Subject: [PATCH 26/31] power: gemini-poweroff: Avoid spurious poweroff
   5
   6 On the D-Link DIR-685 we get spurious poweroff from
   7 infrared. Since that block (CIR) doesn't even have a
   8 driver this can be safely ignored, we can revisit this
   9 code once we have a device supporting CIR.
  10
  11 On the D-Link DNS-313 we get spurious poweroff from
  12 the power button. This appears to be an initialization
  13 issue: we need to enable the block (start the state
  14 machine) before we clear any dangling IRQ.
  15
  16 This patch fixes both issues.
  17
  18 Fixes: f7a388d6cd1c ("power: reset: Add a driver for the Gemini poweroff")
  19 Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
  20 ---
  21 ChangeLog v1->v2:
  22 - Fix both issues and rename the patch.
  23 - Proper commit message with specifics.
  24 ---
  25  drivers/power/reset/gemini-poweroff.c | 30 +++++++++++++++++-------------
  26  1 file changed, 17 insertions(+), 13 deletions(-)
  27
  28 --- a/drivers/power/reset/gemini-poweroff.c
  29 +++ b/drivers/power/reset/gemini-poweroff.c
  30 @@ -47,8 +47,12 @@ static irqreturn_t gemini_powerbutton_in
  31         val &= 0x70U;
  32         switch (val) {
  33         case GEMINI_STAT_CIR:
  34 -               dev_info(gpw->dev, "infrared poweroff\n");
  35 -               orderly_poweroff(true);
  36 +               /*
  37 +                * We do not yet have a driver for the infrared
  38 +                * controller so it can cause spurious poweroff
  39 +                * events. Ignore those for now.
  40 +                */
  41 +               dev_info(gpw->dev, "infrared poweroff - ignored\n");
  42                 break;
  43         case GEMINI_STAT_RTC:
  44                 dev_info(gpw->dev, "RTC poweroff\n");
  45 @@ -116,7 +120,17 @@ static int gemini_poweroff_probe(struct
  46                 return -ENODEV;
  47         }
  48
  49 -       /* Clear the power management IRQ */
  50 +       /*
  51 +        * Enable the power controller. This is crucial on Gemini
  52 +        * systems: if this is not done, pressing the power button
  53 +        * will result in unconditional poweroff without any warning.
  54 +        * This makes the kernel handle the poweroff.
  55 +        */
  56 +       val = readl(gpw->base + GEMINI_PWC_CTRLREG);
  57 +       val |= GEMINI_CTRL_ENABLE;
  58 +       writel(val, gpw->base + GEMINI_PWC_CTRLREG);
  59 +
  60 +       /* Now that the state machine is active, clear the IRQ */
  61         val = readl(gpw->base + GEMINI_PWC_CTRLREG);
  62         val |= GEMINI_CTRL_IRQ_CLR;
  63         writel(val, gpw->base + GEMINI_PWC_CTRLREG);
  64 @@ -129,16 +143,6 @@ static int gemini_poweroff_probe(struct
  65         pm_power_off = gemini_poweroff;
  66         gpw_poweroff = gpw;
  67
  68 -       /*
  69 -        * Enable the power controller. This is crucial on Gemini
  70 -        * systems: if this is not done, pressing the power button
  71 -        * will result in unconditional poweroff without any warning.
  72 -        * This makes the kernel handle the poweroff.
  73 -        */
  74 -       val = readl(gpw->base + GEMINI_PWC_CTRLREG);
  75 -       val |= GEMINI_CTRL_ENABLE;
  76 -       writel(val, gpw->base + GEMINI_PWC_CTRLREG);
  77 -
  78         dev_info(dev, "Gemini poweroff driver registered\n");
  79
  80         return 0;